JLJf^^ 


Reprinted  from  The  Journal  of  Geology,  Volume  III,  Number  6 
September-October,  1 895 


Glacial  and  Inter-Glacial 
Deposits  Near   Toronto 


By  a.  p.  COLEMAN 


a. 

■J  ^ 


CHICAGO 

C|f  «tiQ»cs(tp  of  ®t(Mgo  pMi 


GLACIAL  AND  INTER-GLACIAL  DEPOSITS  NEAR 

TORONTO. 


A  LONG  line  of  yellowish  white  cliffs  to  t^^hc  east  of  the  city 
forms  a  striking  feature  of  the  voyage  across  Lake  Ontario  from 
Niagara  to  Toronto;  and  a  closer  examination  of  the  Scarboro' 
Heights  discloses  a  most  interesting  section  of  the  drift.  At  the 
highest  point  the  cliffs  rise  more  than  300  feet  above  the  lake, 
and  the  thickness  of  the  deposits  is  probably  considerably  greater 
than  this,  for  the  solid  rock  nowhere  crops  out  in  a  distance  of 
twenty  miles.  Along  many  parts  of  the  Heights,  which  are  in  all 
nine  and  a  half  miles  long,  reaching  from  a  point  three  and  a  half 
miles  east  of  the  River  Don  to  the  mouth  of  Highland  Creek, 
the  undermining  action  of  the  lake  provides  for  a  constant 
series  of  fresh  exposures;  and  at  other  points  the  deep  V-shaped 
valleys  of  small  streams,  afford  almost  as  good  sections.  From 
Scarboro'  westwards  to  Toronto  also,  the  cuttings  for  railroads 
and  streets,  and  the  ravines  of  thf>  Don  and  its  tributaries  display 
more  or  less  complete  sections  c  the  drift,  some  of  them  more 
than  150  feet  in  height. 

The  Scarboro'  Heights  were  an  object  of  interest  to  engineers 
and  geologists  more  than  forty  years  ago  as  the  source  of  the 
sand  which,  driving  westwards  along  the  lake  shore,  is  arrested 
by  the  current  of  the  River  Don,  thus  forming  the  island  which 
protects  the  harbor  of  Toronto;'  Init  no  serious  geological  study 
appears  to  have  been  made  of  them  except  by  Dr.  George  Jennings 
Hinde,  who  |)ublished  an  admirable  account  of  them  in  1878.' 
The  results  of  his  observations  seem  little  known,  probably  from 
the  fact  of  their  having  been  published  in  a  journal  not  very 
widely   circulated    and   at  a  time    when   glacial    studies    did   not 

'Reports  011  the  Iinprovenient  and  Preservation  of  Toronto  Harbor,  Prof.  Henry 
Youle  Hind,  p.  i;  Sandford   Fleming,  p.   15;  Appendix  to  Canadian  Journal,  1854-5. 

"Glacial  and  Inter-glacial  Strata  of  Scarboro'  Heights,  Can.  journ.,  1878,  p. 
388,  etc. 

022 


62  3    TORONTO  CLACIAI^  AND  INTER-GLACIAL  DEPOSITS. 

attract  so  much  attention  as  they  now  do,  since  the  rise  of  a  body 
of  able  and  ardent  glacialists  in  America  as  well  as  the  Oid  World. 

The  inter-glacial  beds  of  the  Don  have  been  described  briefly 
by  the  present  writer';  but  beyond  these  two  papers  little  has 
appeared  as  to  the  drift  in  this  part  of  Ontario.  It  seemed  so 
difficult  to  correlate  the  results  obtained  from  these  two  localities 
only  a  few  miles  apart,  that  it  was  decided  to  connect  the  two  by 
a  careful  study  of  the  whole  ground.  This  has  now  been  carried 
out  with  tolerable  completeness,  and  it  is  proposed  here  to  give  a 
short  account  of  the  results.  In  doing  the  work  great  assistance 
has  been  received  from  the  authorities  of  the  Grand  Trunk  and 
Canadian  Pacific  Railways,  who  provided  profiles  of  all  the  lines 
near  Toronto;  from  the  city  engineer,  who  provided  maps;  ar.". 
from  several  specialists  who  have  determined  fossils  obtained 
from  inter-glacial  beds;  and  I  desire  to  express  my  heartiest 
thanks  for  their  great  kindness. 

It  will  be  well  to  begin  with  an  account  of  the  Scarboro' 
Heights  which  afford  the  thickest  and  most  complete  section  in 
the  region.  For  this  my  own  observations,  which  in  general 
accord  well  with  those  of  Dr.  Hinde,  will  be  made  use  of  chiefly. 

The  drift  deposits  show  themselves  first,  after  a  long  stretch 
of  gravel  beach,  about  three  and  a  half  miles  east  of  the  Don,  as 
a  low  clit^  of  stratified  sand  and  sandy  clay,  below  which  blue 
till  appears.  The  first  outcrop  is  just  west  of  Victoria  Park,  and 
the  escarpment,  which  is  only  ten  or  fifteen  feet  high  at  the  begin- 
ning, rises  rapidly,  after  a  break  caused  by  the  valley  of  a  stream, 
to  one  hundred  and  sixty  or  eighty  feet.  About  three  and  a  half 
miles  east  of  the  Park  the  cliff  suddenly  rises  to  a  height  of 
more  than  300  feet,  but  soon  drops  down  to  its  old  level, 
after  v/hich  it  sinks  gradually  to  a  height  of  twenty  or  thirty  feet, 
six  miles  farther  east,  where  it  is  interrupted  by  the  valley  of 
Highland  Creek. 

At  its  best  exposures  the  escarpment  displaj's,  beginning  at 
the  level  of  the  lake,  about  ninety  feet  of  stratified  clay,  followed 

'  Inter-glacial  fossils  from  the  Don  Valley,  Am.  (Jeol.,  Feb.  1894,  P-  *^5>  etc.  In 
this  paper  references  are  given  to  the  literature  on  the  subject,  which  is  very  scanty. 


THE  JOURNAL  OF  GEOLOGY. 


624 


%        by  fifty  feet  of  stratified  sand,  covered  by  a  bed  of 

\j        till  varying  fr  jm  forty  feet  to  nothing  in  thickness. 

e        Three   miles  from   Victoria   Park    this   layer  of  till 

\       suddenly  dips  down  to  the  lake,  thickens  to  sixty 

■^        or  seventy  feet,  and  rises  as  suddenly  a  quarter  of  a 

mile  farther  cast.     The  hollow  left  on  its  surface  is 

filled  with  stratified  clay  to  a  depth  of  ninety  feet, 

and  this  is  followed,  where  the  escarpment  is  high- 

"4   est,  a  half  mile  farther  cast,  by  from  seventy  to  one 

f    hundred  feet  of  stratified  clay  and  sand,  capped  by 

^    twenty   or   thirty   feet  of  an  upper  till.     About  one 

O 

°  hundred  feet  of  stratified  sand  overlying  the  western 

S  end  of  the    lower  sheet   of   till,  should   perhaps   be 

^  correlated  with  this,  though  possibly  of  post-glacial 

■^  aire.     These  sands   thin   out  to  nothing  where   the 

I  ujjper  stratified  clay  shows  itself.     The  accomj^any- 

-N  ing  diagram,  in  which  the  heights  are  exaggerated 

i  tenfold,  will  give  a  general  idea  of  the  section  and 

^  make  a  more  elaborate  description  unnecessary.      It 

7"  will  be  noticed  that  the  lower  bed  of  till  dips  down 

•g  o  to  the  lake  at  each  end   of  the   section  ;   while  the 


^  g    ui)per  till,  forming  the  surface  of  a  table  land  which 

-g  -g    comes  out  to  the  escarpment  for  a  short  distance 

"3   c 
Q  .2 


only,  is  cut  off  abrui)tly  at  each  end. 

Examining  the  members  of  this  section  in  ascend- 
ing order,  we  find  at  its  base  a  series  of  bluish-gray 
clays  rising  out  of  the  lake.  They  lie  perfectly 
horizontal,  arc  often  finely  laminated  with  sandy 
partings,  having  sometimes  twenty  lamin;e  to  an 
inch,  but  at  other  times  forming  beds  several  feet  in 
thickness.  Narrow  bands  of  flat  green  concretions 
of  impure  carbonate  of  iron  occur  at  various  levels  ; 
and  at  others  thin  layers  of  peaty  matter.  Some 
beds  of   cla\-  richer  than  others   in  plant  food  may 

be  followed  long  distances  by  the   eye  as  bands   of  rich,  green 

vegetation,  while  other  parts  are  bare. 


II 


62  5     TORONTO  GLACIAL  AND  INTER-GLACIAL  DEPOSITS. 

The  ])caty  matter  varies  froin  a  mere  film  to  a  thickness 
rarely  greater  than  half  an  inch,  and  is  made  up  sometimes 
chiefly  of  mosses,  but  more  commonly  of  fragments  of  bark, 
wood  and  twigs,  waterworn  and  mingled  with  flakes  of  mica. 
Quite  seldom  one  may  find  a  larger  knot  or  broken  branch,  but 
never  trunks  of  any  size.  From  these  insignificant  peaty  layers 
Dr.  Hinde  obtained  three  species  of  diatoms,  a  chara,  five  mosses, 
Bryum,  Fontinalis,  Hypnum  commutatum,  II.  revolvens  (?)  and 
another  species  of  hypnum,  spores  of  lycopodium,  pieces  of  pine 
and  cedar  wood,  portions  of  leaves  of  rush,  etc.,  and  seeds  of 
various  plants.  Among  animals  he  found  two  or  three  species 
of  Cypris,  a  Planorbis  and  a  Zonites  (doubtful),  as  well  as  the 
elytra  of  beetles.'  The  insect  remains  v^^ere  submitted  to  Dr. 
Scuddcr,  who  reports  as  follows  :^ 

"Among  the  material was  a  considerable  number  of 

the  elytra  and  other  parts  of  beetles,  an  assemblage,  indeed  larger 
than  has  ever  before  been  found  in  such  a  deposit  in  any  part  of 
the  world,  and  they  are  mostly  in  excellent  condition.  Twenty 
nine  species  have  been  obtained,  some  of  them  in  considerable 
numbers.  Five  families  and  fifteen  genera  are  represented;  they 
are  largely  carabid:e,  there  being  six  or  seven  species  each 
of  Platynus  and  Pterostichus  and  species  also  of  Patrobus, 
Bembidium,  Loricera,  and  Elaphrus.  The  next  family  in  impor- 
tance is  the  StaphylinidK,  of  which  there  are  five  genera,  Gcodro- 
micus,  Arpedium,  Bledius,  Oxyporus,  and  Lathrobium,  each 
with  a  single  species.  The  Hydrophilida;  arc  represented  by 
Hydrochus  and  Heloi)horus  with  each  one  si)ecies;  and  the 
Chrysomelidx  by  two  species  of  Donacia.  Finally  a  species  of 
Scoiytidai  must   have   made  certain  borings  under  the  bark   of 

juniper. 

"  Looking  at  them  as  a  whole  and  noting  the  distribution  of  the 
species  to  which  they  seem  to  be  most  nearly  related,  they  arc 
plainly  indigenous  to  the  soil,  but  would  perhaps  be  thought  to 
have  come  from  a  somewhat  more  northern  locality  than  that  in 

■  Can.  Jour.  1878,  p.  399- 
•  'Fossil  Insects  of  North  America,  Vol.  II.,  Teitiary,  p.  40, 


THE  JOURNAL  OF  GEOLOGY.  626 

which  they  were  found;  not  one  of  them  can  be  referred  to  exist- 
ing species,  but  the  nearest  allies  of  not  a  few  of  them  are  to  be 
sought  in   the  Lake  Superior  and  Hudson  Bay  region,  while  the 
larger  part  are    inhabitants  of  Canada   and   the  northern  United 
States,  or  the  general   district  in  which  the   deposit   occurs.      In 
no  single  instance  were   any   special   affinities  found  with    any 
characteristically  southern  forms,  though  several  are  most  nearly 
allied  to  species  found  there  as  well  as  in  the  north.     A  few  seem 
to  be  most  nearly  related  to  Pacific   forms,  such  as  the  Elaphrus 
and  one  each  of   the  species  of   Platynus  and    Pterostichus.     On 
the  whole,  the  fauna  has  a  boreal  asjiect,  though  by  no  means  so 
decidedly   boreal   as   one   would    anticipate   under    the    circum- 
stances." 

It  will  be  seen  that  this  remarkable  assemblage  of  insects  is 
of  great  importance  in  coming  to  a  conclusion  as  to  the  climate 
of  the  time  when  these  deposits  were  laid  down;  and  Dr.  Scudder's 
wide  experience  in  regard  to  the  geographical  range  of  North 
American  insects  gives  special  value  to  his  views  on  the  subject. 
By  washing,  drying,  and  examining  with  a  lens  peaty  matter 
from  Scarboro'  the  present  writer  has  succeeded  in  obtaining  a 
large  amount  of  additional  material,  consisting  of  wing  cases  and 
other  parts  of  the  chitinous  armor  of  insects,  all  of  which  has 
been  submitted  to  Dr.  Scudder,  who  has  very  kindly  consented 
to  determine  them  and  thus  add  to  the  data  available  for  judging 

of  the  climate. 

A  considerable  number  of  determinable  parts  of  plants,  such 
as  leaves,  seeds,  mosses,  etc.,  obtained  in  the  same  way,  was  sent 
to  Dr.  Macoun  of  Ottawa.  The  small  collection  of  mosses  was 
forwarded  by  him  to  Mrs.  E.  G.  Britton  of  Columbia  College, 
New  York;  and  I  am  much  indebted  to  both  of  them  for  the 
trouble  they  have  bestowed  on  the  determinations.  Dr.  Macoun 
gives  the  following  list  of  the  species  determined  by  him  in  the 
material  sent:  Larix  americana  (?),  Abies  balsamea,  Salix,  alder, 
Carex  aquatilis  and  C.  utriculata,  Equisetum,  Oxycoccus  vulgaris 
and  vaccinium  uliginosum.  Of  the  last  two  he  is  quite  certain. 
Mrs.  Britton  determines   the  mosses  as  follows:  Limnobium 


t)27    TORONTO  GLACIAL  A  A'/)  L\'TKR-GLACL\L  DEPOSITS. 

jKilustrc  (?),  L.  montanum  (?),  llypniini  lycopodioidcs  (?),  II. 
adunciim,  H.  tluitans  (?).  Professor  I'cnhallow  of  Montreal  has 
determined  two  specimens  of  wood  from  Scarboro'  as  probably 
Picea  nigra. 

It  will  be  noticed  that  the  plants  obtained  by  myself  differ 
considerably  from  the  list  given  by  Dr.  Ilinde,  perhaps  because 
taken  from  different  levels  in  the  clay.  Doubtless  the  number 
of  species  could  be  greatly  added  to  by  careful  search. 

Looking  at  the   plants  as   a  whole  Dr.    Macoun   is  of  opinion 
that  the  climate  was  like  that  of  the  northern  part  of  the  Gulf  of 
St.  Lawrence  or  southern  Labrador,  cool  and  wet.   He  states  that 
all  the  species  are  represented  in  the  herbarium  of  the  Geological 
Survey  at  Ottawa  by  specimens  from  the  regions  mentioned;  and 
thinks  that  the  deposit  was  formed  in  a  pool  surrounded  by  trees, 
such  as  we   find   in    our   northern    woods   today.      Dr.  Macoun's 
conclusions  regarding  the  climate  as  determined  from  the  plants 
correspond   fairly  well  with   those   of    Dr.   Scudder;    so  that  the 
(juestion  may  be  looked  upon  as  settled.    There  are,  however,  no 
evidences  of  the  action  of  ice.     Dr.  Hinde  remarks  the  comi)lete 
absence  of  i)ebbles  or  bowlders  from  these  clay  beds,  a  point 
which  the  present  writer  also   has   been   struck  with,   suggesting 
no  transport   and    dropjjing   of   materials   by    floating  ice.      One 
may  infer  from    the   uniform   lamination  and  fineness  of  the  clay 
that   it   was  deposited    in   (|uiet   water  some    distance   from    the 
shore.    Leaves  and  bits  of  bark  and  mosses  drifted  in  by  the  wind 
or  brought   down  by  a  stream    gradually   waterlogged   and   sank 
along  with  the   slowly   settling   flakes  of  mica  and  fragments  of 
insects.     It  appears   that   forest  fires  raged   in   Ontario  then  as 
now,  for  fragments  of  charcoal  or  of  chips  charred  on  one  edge 
are  not  infrequently  found  mixed  with  quite  uncarbonized  woody 
material.  This,  of  course,  does  not  necessarily  imply  the  presence 
of  man;    for   doubtless    many   fires   have  originated    by    natural 
causes,  such  as  lightning. 

Resting  conformably  on  the  clay  we  find  about  fifty  feet  of 
fine,  yellowish  or  grayish  sand,  sometimes  having  thin  layers 
reddened    with    garnets     or    blackened    with    magnetite.     Very 


THE  JOURNAL  OF  GEOLOGY.  628 

marked  transverse  beddinj;  is  often  observed,  indicalinj^^  more 
troubled  water  than  during  the  deposit  of  the  underlying  clay. 
Some  parts  of  these  sands  contain  many  nut-brown  concretions 
of  a  much  rounder  form  than  those  from  the  clay.  A  large 
number  of  these  were  broken,  but  only  two  or  three  contained 
traces  of  vegetable  matter  or  |)ortions  of  insects  as  a  nucleus. 
Peaty  matter  may  be  found  in  small  amounts  in  the  sand,  and  at 
a  few  points  fresh-water  shells  were  found  along  with  the  con- 
cretions, Sphicrium  striatinum  and  Succinea  obliqua,  according  to 
determination  of  Mr.  C.  T.  Simpson.  The  Succineas  seem  almost 
too  fresh  and  well  preserved  to  be  of  inter-glacial  age,  but  they 
are  found  nowhere  except  in  the  sand  beds  below  the  lower  till, 
and  the  evidence  of  their  age  seems  pretty  conclusive. 

The  beds  just  described  were  deposited  in  water  having  a 
level  at  least  140  feet  above  that  of  the  present  Lake  Ontario; 
and  they  may  have  been  considerably  thicker  than  we  find  them 
now,  for  there  is  clear  evidence  that  they  were  greatly  eroded 
before  the  overlying  till  was  spread  out.  At  the  Dutch  Church 
not  only  the  sands  but  the  stratified  clays  also  were  cut  through 
by  a  stream  valley,  for  we  find  the  bowlder  clay  filling  a  hollow 
that  reaches  below  the  level  of  the  lake.  Hindc  supposes  that 
the  ice  of  the  glacier  ploughed  out  this  deep  valley;  but  there  is 
no  reason  to  suppose  that  this  portion  only  should  have  been 
excavated  by  the  ice  front  while  the  same  materials  were  left 
untouched  on  each  side.  The  bedding  of  the  clay  is  scarcely 
distuibed  right  up  to  the  contact  with  the  till,  which  would  be 
impossible  if  the  snout  of  the  glacier  had  ploughed  its  way 
through,  but  is  intelligible  if  it  simply  filled  a  preexisting  valley. 

The  till  which  follows  is  of  the  usual  description,  a  blue 
calcareous  clay  charged  with  polished  and  striated  pebbles  of  lime- 
stone and  black  Utica  shale,  with  p  few  Laurentian  bowlders. 
This  bed  of  till  is  continuous  from  end  to  end  of  the  section 
except  at  a  point  about  one  mile  and  a  half  east  of  Victoria  Park, 
where  probably  by  subsequent  erosion,  it  is  thinned  out  to 
nothing  for  about  300  yards.  There  is  a  deep  hollow  in  the  till  at 
the  Dutch  Church,  where   it   dips   down  to  the    lake,  jjerhajjs  an 


62g    TORONTO  GLACIAL  AND  INTER-GLACIAL  DEPOSITS. 

oritT'inal  ilcprcssion  of  its  surface,  now  filled  with  ninety  feet  of 
stratified  clay,  very  like  the  lower  beils,  but  more  calcareous  and 
apjjarently  free  from  fossils  and  concretions. 

At  the  jjoint  where  the  ui)|)er  terrace  comes  out  to  the  shore 
these  stratified  clays  are  covered  conformably  by  a  series  of 
stratified  sands  with  some  clay  beds,  in  all  seventy  feet  thick. 
Several  of  these  beds  at  different  levels  are  remarkably  crum})led 
and  contorted,  while  the  beds  immediately  above  and  below 
a])])ear  (juite  undisturbed.     They  have   perhaps  been   folded   by 


Upi)er  i)art  of  Section  at  Scailxiru'  Heights,  showini,'  two  upper  layers  of  till  ami 
tlie  crumpled  strata.     After  photograph  by  Dr.  Ellis, 

the  grounding  of  ice  floes,  and  in  ai)pearance  they  remind  one  of 
examples  figured  in  Gci/cic's  Gnat  Ice  Agc.^  No  fossils  have 
been  obtained  from  these  inter-glacial  beds. 

The  upper  till,  which  overlies  the  country  to  the  north  of  the 
Scarboro'  Heights,  forming  a  gently  rolling  table-land,  describetl 
by  Professor  Chamberlin  in  conversation  as  a  mild  form  of  moraine, 
is  seen  at  this  section  to  consist  of  yellowish-brown  clav  with 
well  striated  j)ebbles  and  larger  stones,  fragments  of  black  I'tica 
shales,  often  falling  to  pieces,  limestones  apparently  of  Trenton 
age,  and  archiean  rocks,  such  as  gneisses.  It  differs  fiom  the 
lower  till  in  being  somewhat  more  sandy,  and  esj)ecially  in  hav- 

'  1'.  271-2. 


THE  JOURNAL  OF  GEOLOGY.         .  630 

ing   been   greatly   weathered,  some    i)arts   at    the  bottom  alone 
showing  the  original  blue  color  of  the  clay. 

West  of  this  highest  part  of  the  escarpment  a  series  of 
rather  coarse,  cross-bedded,  stratified  sands  and  gravels,  in  which 
no  fossils  have  been  found,  overlies  the  lower  till,  at  first  in  a 
a  thin  layer,  but  rapidly  thickening  as  the  bed  of  till  descends 
toward  the  lake  near  Victoria  Park,  where  it  ex[Kinds  to  a  thick- 
ness of  more  than  one  hundred  feet.  Hinde  looks  on  these  sands 
and  gravels  as  post-glacial,  but  similar  deposits  a  few  miles  to 
the  west  and  north  are  covered  bv  the  upper  till;  and  at  a  cutting 
on  theScarboro'  street  railway  a  little  north  of  the  Park  crumpled 
strata  of  the  kind  pre\iously  referred  to  are  well  exposed,  suggest- 
ing an  inter-glacial  age  for  these  beds.  However  up  to  the  present 
their  position  must  be  looked  on  as  not  [)ositivcly  settled. 

A  com|)aratively  thin  layer  of  coarse  gravel  and  well-rountled 
stones,  followed  by  loamv  soil  covers  these  sands  and  forms  the 
surface  of  the  Irocpiois  terrace. 

From  the  descri})tion  just  given  it  will  be  seen  that  at  the 
Scarboro'  Heights  there  are  two  beds  of  till  separated  by  a  deposit 
of  unfossilifcrous  stratified  clay  and  sand  amounting  in  thickness, 
if  we  add  the  dejith  of  stratified  clay  at  the  Dutch  Church  to  that 
of  santl  and  clay  at  highest  points  a  little  farther  east,  of  160 
feet.  Below  the  lower  till  the  fossiliferous  sands  and  clays  have 
a  depth  of  at  least  140  feet,  their  lower  limit  being  covered  by 
the  lake.  Dr.  Hinde  assumes  a  third  till  below  the  lower  clay, 
nowhere  exposed  along  the  Scarboro'  escarpment,  but  cropping 
twelve  miles  to  the  west  at  H umber  Bay,  where  till  overlies  the 
Hudson  River  shales,  and  is  covered  by  stratified  clay  not  unlike 
that  at  Scarboro'.  The  Humber  clays,  so  far  as  I  have  observed, 
do  not  contain  peaty  matter  nor  the  i)late-like  concretions  of  clay- 
iron  stone;  however,  they  arc  so  far  separated  that  the  conditions 
under  which  they  were  deposited  may  have  differed  greatly 
from  those  at  Scarboro'. 

Whether  the  underlying  till  be  found  or  not,  there  is  every 
reason  to  think  the  lower  Scarboro'  sands  and  clays  inter-glacial; 
for  they  contain  a  scries  of  minerals  incUuling  garnet,  magnetite, 

» 


6^1     TORONTO  GLACIAL  AND  INTER-GLACIAL  DEPO  UTS. 

hornblende  and  biotitc,  thoroughly  characteristic  of  Laurentian 
rocks  and  not  found  in  the  adjacent  Hudson  River  or  Utica 
shales.  The  transport  of  these  materials  for  a  distance  of  not 
less  than  seventy  miles  is  best  accounted  for  by  glacier  ice. 

The  extent  of  these  deposits  has  not  yet  been  worked  out  in 
detail,  though  the  lower  stratified  clay  was  apjiarently  wide- 
spread. Twenty  feet  of  clav  very  like  it,  containing  thin  layers 
of  peaty  matter,  may  be  seen  on  the  shore  of  Lake  Ontario  four 
miles  to  the  east  of  Highland  Creek,  here  also  covered  by  a  bed 
of  till.  Exactly  similar  clay  occurs  about  four  miles  to  the  north- 
west of  Victoria  Park  in  the  brickyards  of  Messrs.  Price  and 
Logan.  The  exposures  are  excellent,  one  presenting  a  face  of 
sixty  feet;  and  the  to|)  of  the  clay,  which  rises  about  one 
hundred  feet  above  Lake  Ontario,  is  covered  with  a  few  feet  of 
stratified  sand.  One  finds  the  greenish  plate-like  concretions, 
and  peaty  matter  containing  mosses,  pieces  of  bark  and  wood, 
elytra  of  beetles,  flakes  of  mica,  etc.,  just  as  at  Scarboro'.  The 
layer  of  till  is  wanting  at  these  brickyards,  but  is  found  a  few 
hundred  yards  farther  north  near  the  corner  of  Danforth  avenue 
and  Greenwood  lane. 

If  we  include  the  Humbcr  clay  in  the  series,  this  lacustrine 
deposit  has  a  length  of  twenty  two  miles,  by  a  breadth  of  at  least 
one  and  one  half  miles.  Omitting  the  Humber  beds,  it  has  been 
traced  for  about  sixteen  miles. 

The  upper,  unfossiliferous  clay  from  the  Dutch  Church  seems 
also  very  widely  distributed.  It  may  be  found  as  suggested  by 
Dr.  Hinde,  in  the  north  of  Toronto  (formerly  Yorkville),  where 
it  is  used  to  make  gray  brick.  It  seems  to  occur  also  at  the 
Don  Valley  brickworks,  and  other  points  along  the  Don  ravines. 
Similar  stratifietl  unfossiliferous  clays  making  white  or  buff  or 
gray  brick  occur  at  various  j)oints  a  few  miles  to  the  north  and 
west  of  Toronto  ;  and  beds  very  like  them  underlying  an  upi)er 
till  are  well  exj)osed  on  the  lake  shore  between  Newcastle  and 
Newtonville,  more  than  forty  miles  to  the  east.  The  u|)|)er 
unfossiliferous  clays  a|)pear  then  to  be  even  more  wiilely  spread 
than  the  lower  peaty   clays,   though   one  can  hardly  make  sure 


THE  JOURNAL  OF  GEOLOGY.  632 

that  the  deposits  at  all  the  localities  mentioned  were  laid  down 
in  the  same  body  01  water  and  at  exactly  the  same  time. 

The  inter-glacial  deposits  on  the  Don,  best  shown  at  the 
brickworks  owned  by  the  Messrs.  Taylor,  were  described  a  year 
ago,'  but  will  be  referr'  I  to  again,  giving  the  results  of  a  careful 
reinvestigation  under  better  conditions. 

When  it  was  examined  in  the  preparation  of  the  paper  referred 
to,  the  cjuarry  consisted  of  two  i)arts,  a  lower  one  showing  about 
forty  feet  of  drift,  including  nearly  three  feet  of  till   resting  on 
Hudson  River  shale,  twenty-five  feet  of  stratified  sand  with  one 
or  two    clay   beds,    and,    above   this,   ten    feet   of  stratified  clay 
making  red  brick.    A  slope  of  grass  extended  from  tliis  part  of  the 
cpiarry  for  about  one  hundred  yards  to  the  upper  portion,  where 
about  forty  feet  of  stratified  clay  making   buff  brick  were  •'o  be 
seen,  the  top  of  the  exposure  reaching  almost  to  the  level  of  the 
plain  formed  by  the  Iroquois  beach  of  Spencer.     The  part  cov- 
ered with  grass  was  stated  by  the  men  at  work  in  the  quarry  to 
consist  of  the  same  clay  as  that  worked  for  buff  brick,  i  nd  was 
included    with    the    upper    stratified    clay    in   the   section  given. 
About  a  third  of  a  mile  northwest  of  the  (piany    the  Davenport 
Ridge,  a  morainic  tract  of  gently  rolling  highland,  comjjosed  of 
somewhat   sandv    till    containing   bowlders  and   striated   stones, 
comes  to  a  sudden  .^lop  and  forms   a   cliff   fifty   to    seventy   feet 
high  at  the  Iroquois  beach.     That  the    Davenport   till    stretched 
much  farther  south  before   the    Irocjuois   water   had   encroached 
upon   it   is   clear,   not   alone    from    the  steep  cliff    but  from   the 
immen;;e    bowlders  scattered    over    the    terrace,    evidently     left 
behind   when    the    finer   materials   were   washed   away  by  wave 
action.     Such  bowlders  lay  on  the  surface  just  above  the  cpiarry, 
until  removed  a  year  ago.      The    fact    that   the    ui)[)er   stratified 
clay  of  the  cpiarry  may  be  traced  hero  and  there  up  the  ravine  to 
the  north,  until,  about  half  a  mile  above  the  brickyard,   it  under- 
lies the  till  of  the  Davenport  ridge,  confirms  the  conclusion. 
The  Daveniiort  ridge  is  a  continuation  of  the   mild   moraine 

■  Inler-Klucial    fossils    In.m    the    Don    ViUlev,    Am.   Clcol.   \nl.    Xlll.,    I'cl.niaiy 
1894,  p.  05-95. 


633    TORONTO  GLACIAL  AND  INTER-GLACIAL  DEPOSITS. 

forming  the  upper  plateau  at  Scarboro',  the  two  being  separated 
only  by  the  deej)  bay-like  depression  of  the  Don  Valley  ;  and  it 
seemed  to  me  probable,  last  year,  that  the  layer  of  till  overlying 
the  shale  at  the  brickyard  was  a  continuation  of  the  lower  Scar- 
boro' till,  which  :iinks  beneath  Lake  Ontario  near  Victoria  Park- 
three  or  four  miles  to  the  east.  This  implied  that  the  fossilifer- 
ous  beds  at  the  Don,  with  the  overlying  stratified  clay  in  which 
no  fossils  occur,  were  equivalent  to  the  upper,  unfossiliferous 
beds  at  Scarboro'.  This  spring,  however,  new  excavations  at  the 
brickyard  have  completely  overturned  this  theory  by  disclosing 
a  thick  bed  of  till  in  the  slope  formerly  covered  with  grass.  This 
overlies  the  fossil-bearing  strata  which  correspond,  therefore,  to 
to  the  lower,  fossiliferous  bed  at  Scarboro',  so  far  as  position  is 
concerned. 

At  present  the  cpiarry  presents  the  following  sectio"  as  meas- 
ured by  aneroid  and  steel  tape  : 

"'eet. 

Soil  and  stratified  clay,  making  buff  biick  (unfossiliferuus)  43 

Till  (partly  covered  with  f^rass)  about            -              -           -  .35 

Stratilied  clay  with  peaty  matter,  making  red  brick       -  13 

Stratified  sand  with  some  clayey  beds  (fossiliferous)             -  24 

Till          -            -             -            "-             -             -             -  2 

Hudson  River  shales,  about              -              -              -             -  60 

The  Hudson  River  shales  rise  about  thirty-five  feet  above  the 
level  of  Lake  Ontario.  At  the  Don  Valley  brickworks  we  have, 
then,  a  lowest  till  resting  on  the  rock  and  overlaiil  with  fossilif- 
erous beds ;  a  second  till  corresponding  to  the  lower  Scarboro' 
till;  but  no  uppermost  till,  though  one  probably  existed  before 
the  formation  of  the  Irocjuois  beach,  and  the  upper  stratified  clay 
passes  beneath  the  upper  till  at  the  Davenport  ridge  a  half-mile 
away.  So  far  as  I  have  observed  the  three  tills  are  nowhere  all 
disclosed  in  a  single  section  ;  but  a  shaft  sunk  through  the  Daven- 
port ridge  or  the  highest  part  of  the  Scarboro'  Heights  would 
probably  cut  through  all  three. 

Since  the  [)aper  on  the  Don  fossils  was  published  three  new 
localities  have  been  found  in  the  same  valley;  one  of  them, 
which  was  opened  to  give  employment  to  the  convicts  at  the  gaol 


THE  JOURNAL  OF  GEOLOGY. 


634 


near  by,  j)roving  especially  intercstini^ ;  since  thin  layers  of  mat- 
ted deciduous  leaves  occur  in  it.  One  of  these  localities  is  at 
the  shore  of  a  pond  a  mile  above  the  brickyard,  so  that  the  fos- 
sil-bearint^  sands  and  clays  have  been  shown  to  extend  for  three 
miles  alouiT  the  valley  of  the  Don.  Judgint^  by  the  j)osition  of 
these  beds  with  reference  to  the  lake,  the  stream  in  which  they 
were  formed  had  a  much  more  rapid  fall  than  the  present  slug- 
gish river.     The  lowest  fossil  bed  in  the  up])er  ])art  of  the  valley 


Ijuaiiy  111  'I'liylor's  brickyard,  Don  Valley,  'roronto.  'llic  section  .sliows  tiie  Hud- 
son River  sliale  ;  llie  lowest  till  resting  on  it  (dark);  the  fossiliferous  stratitied  sand 
and  clay  ;  the  middle  till  just  beneath  the  grass  at  the  staging  ;  and  the  upper  strati- 
fied unfossiliferous  clay  in  the  much  foreshortened  upper  ipiarrv.  The  |)iiologra|)h  is 
by  Dr.  Ellis,  of  the  ScIkjoI  of  Practical  Science,  Toronto. 


is  about  forty  feet  above  the  lake  ;  at  the  Convict  Cutting  ten  or 
fifteen  feet ;  while  at  the  cutting  for  the  Don  improvements,  near 
the  mouth  of  the  present  river,  fossils  were  found  several  feet 
below  the  level  of  Ontario. 

The  localities  most  produeti\e  in  fossils  are  the  brickyard  and 
the  Convict  Cutting,  and  a  brief  description  of  them  may  be  of 


635    TORONTO  GLACIAL  AND  INTER-GLACIAL  DEPOSITS. 

interest.  At  the  brickyard  unios,  retainiiiir  their  dark  epidermis 
and  havinj^  the  valves  united,  are  often  found  embedded  in  a  few 
inches  of  blue  clay  immediately  ovcrlving  the  till.  The  sands 
above  this  contain  more  or  less  waterworn  unios,  pleuroceras, 
sphieriunis,  etc.,  while  the  overlying  stratified  clay  beneath  the 
middle  till  holds  a  little  peatv  matter,  but  nothing  well  enough 
preserved  to  be  determinable. 

At  the  Convict  Cutting,  too,  the  unio  bed  is  disclosed,  but 
some  stratified,  sandv  clav  beils  in  the  upj)cr  part  of  the  section 
have  proved  much  more  interesting,  that  patient  collector,  Mr. 
Townsend,  having  obtained  from  them  a  large  number  of  leaves, 
among  which  he  thinks  are  leaves  of  the  oak,  beech  and  willow. 
It  is  verv  difficult  to  preserve  these  leaf  fragments,  since  the  clay 
dries  up  and  the  brown  traces  of  the  outline  and  veining  shrivel 
up  and  become  almost  unrecognizable. 

Up  to  the  present  the  unios  have  proved  the  most  important 
finds  along  the  Don.  They  include  the  Unio  phaseolus,  U.  clavus, 
U.  pustulosus,  U.  pustulosus,  var.  schoolcrafti,  U.  occidcns  (?), 
U.  luteolus,  U.  undulatus,  U.  rectus,  U.  trigonus,  and  U.  solidus. 
The  other  shells  obtained  are  .Sph;trium  striatinum,  Pleurocera 
subulare,  P.  elevatum,  an  undetermined  species  of  the  same  genus 
and  a  single  specimen  which  may  be  V.  pallidum,  I'livsa  ancil- 
laria  and  Amnicola  limosa.  I  am  indebted  to  Dr.  Dall  and  his 
assistant,  Mr.  C.  T.  .Simpson,  for  the  determination  of  the  above 
species,  all  of  which  occur  at  the  brickyards  and  several  of  them 
at  the  other  points.  A  few  other  fossils,  including  one  or  two 
species  of  ostracods,  a  number  of  elytra  of  beetles  and  one  or  two 
teeth,  the  latter  found  bv  Mr.  Townsend,  have  been  obtained  at 
the  Convict  Cutting  with  the  leaves,  but  have  not  yet  been  deter- 
mined. 

The  plants  include  fragments  of  tree  trunks,  leaves,  a  very 
few  mosses  and  chara.  The  specimens  of  wood  have  been 
determined  by  Professor  Penhallow  of  McGill  to  be  P'raxinus 
(]uadrangulata,  Quercus  obtusiloba,  Ulmus  americana,  Madura 
aurantiaca  and  Picea  sitchensis  (r).  Some  leaves  sent  from  the 
Convict  Cutting  he  considers  to  be  of  willows  and  poplars.     Pro- 


THE  JOURNAL  OF  GEOLOGY.  636 

fessor  Penhallow  had  previously  found  in  material  sent  by  Mr. 
Townscnd  from  the  Don  Improvements,  Asimina  triloba,  Ulmus 
racemosa,  Taxus  baccata  and  a  new  maple  leaf,  which  was  named 
Acer  pleistocenicum.'  In  respect  to  the  woods,  Professor  Pen- 
hallow  says  that  they  are  usually  badly  decayed,  but  that  he  has 
referred  them  to  the  nearest  living  species. 

If  we  compare  the  inter-glacial  fossils  of  the  Don  with  those 
of  Scarboro'  we  find  them  surprisingly  different.  Up  to  the  pres- 
ent only  one  species  of  animal,  Sphiurium  striatinum,  a  form 
having  a  wide  range,  has  been  shown  to  be  common  to  both 
localities.  It  will  be  of  great  interest  to  learn  if  Dr.  Scudder 
finds  insects  from  the  Convict  Cutting  the  same  as  those  from 
Scarboro'  or  not.  No  two  trees  are  undoubtedly  alike,  though 
Picea  nigra  of  Scarboro'  is  not  far  removed  from  Picea  sitchensis 
of  the  Don  ;  and  willow  leaves  of  undetermined  species  have 
been  found  in  both  places. 

It  will  be  remembered  that  both  the  insects  and  plant  remains 
of  Scarboro',  in  the  opinion  of  such  good  authorities  as  Dr.  Scud- 
der and  Dr.  Macoun,  point  to  a  cool  climate  like  that  of  Lake 
Superior  or  Labrador ;  while  the  Don  fossils,  on  the  other  hand, 
point  equally  conclusively  to  a  climate  as  warm  as  that  of  Toronto 
at  present,  if  not  considerably  warmer.  The  numerous  unios, 
some  of  them  no  longer  found  in  our  lakes,  though  common  far- 
ther south  in  the  Mississippi  drainage  system  ; "'  the  forest  trees 
including  three  sj)ecies  (Asimiana  triloba,  the  osagc  orange  and 
P>axinus  c|uadrangulata)  now  belonging  to  the  portions  of 
Ontario  along  Lake  Erie  and  the  states  to  the  south, 3  hint  at  a 
climate  very  far  from  glacial,  probably  comparable  to  that  of 
Ohio  at  present. 

There  seems  no  doubt  also  that  both  of  these  deposits  are 
inter-glacial  and  included  between  the  same  sheets  of  till ;  though 
the  lowest  till  is  out  of  sight  below  the  lake  at  Scarboro'.  These 
two  series  of  beds  can  hardly  have  been   formed  contempora- 

■  15ull.  Geol.  Soc.  .\ni.,  Vol.  I.,  |>.  .^28. 

''C.  T.  SiMi'SON,  I'roceedings  U.  S.  National  .Mus.  Vol.  .\VI.,  pj).  S'H-S- 

3Dr.  Macoun,  Forests  of  Canada,  Trans.  Royal  Soc.  Can.,  Sec.  IV.,  1894,  p.  1 1, 


637    TORON'^'O  GLACIAL  AND  INTER-CLACIAL  DEPOSITS. 

ncously;  one  must  have  preceded  the  other;  but  which  came  first 
is  not  easy  to  decide. 

One  mi^ht  assume  that  the  Scarboro'  clays  were  formed  first, 
a  cold  climate  continuing  for  a  long  [)eriod  of  time  after  the 
departure  of  the  earliest  ice  sheet ;  that  the  water  was  drained  ofi 
or  the  land  elevated  afterwards,  and  the  Don  of  those  days  exca- 
vated its  comparatively  wide  and  deep  valley  apparently  not 
greatly  different  from  the  present  one.  Meantime  the  climate 
had  become  warm,  and  southern  forms  of  life  pushed  their  way 
northward  and  occupied  the  river  and  its  shores  until  the  second 
advance  of  ice  destroyed  them.  This  hypothesis  seems  to  agree 
with  many  of  the  facts,  particularly  if  Dr.  Hinde  is  correct  in  his 
belief  that  the  stratified  clay  resting  on  till  near  the  mouth  of  the 
1  lumber  is  a  continuation  of  the  fossiliferous  Scarboro'  beds. 
The  quite  similar  cla^-s  at  Price's  brickyard  would  then  be  a  rem- 
nant of  a  wide  sheet  of  such  lacustrine  deposits  afterward  eroded 
by  the  Don.  There  is  an  ai)pearance  of  interbedding  of  a  thin 
layer  of  the  peaty  clay  at  the  Taylors'  brickyard  with  the  bowl- 
der-clay above  ;  while  the  upper  fossiliferous  beds  at  Scarboro' 
were  much  eroded  before  this  sheet  of  till  was  laid  down,  facts 
which  perhaps  point  in  the  same  direction.  If  this  hypothesis  be 
correct  the  Don  beds,  being  much  later  than  those  of  Scarboro', 
may  somewhere  be  found  resting  unconformably  on  their  eroded 
surface.  Up  to  the  present,  however,  no  such  section  has  been 
observed. 

On  the  other  hand  one  might  suppose  that  the  Don  beds  are 
the  older ;  that  after  the  till  was  laid  down  there  was  a  sudden 
change  of  climate,  and  that  southern  forms  of  life  quickly  fol- 
lowed uj)  the  retreat  of  the  ice-sheet  as  it  vanished  under  the 
action  of  warm  sun  and  winds.  The  fact  that  Mississipjii  unios 
lived  and  died  right  on  the  unweathered  surface  of  the  blue  till 
at  the  brickyard  fits  best  with  this  assumption.  If  there  had  been 
a  long  period  of  erosion  before  they  arrived,  one  would  expect 
to  find  the  till  wcatnered  brown  and  its  enclosed  pebbles  of  shale 
crumbled  to  pieces,  instead  of  being  fresh  and  sharply  striated. 
Taking  this  view,  the  layer  of  peaty  clay  just  beneath  the  middle 


THE  JOURNAL  OF  GEOLOGY.  638 

till  at  the  Don  is  the  equivalent  of  the  ninety  or  more  feet  of 
peaty  clay  at  Price's  brickyard  and  Scarboro' ;  and  one  niig-ht 
expect  to  find  the  iinio  bed,  or  its  equivalent  as  to  climate, 
beneath  the  level  of  the  lake  at  Scarboro'.  It  should,  however, 
be  observed  that  up  to  the  present  no  species  has  been  shown  to 
be  common  to  the  peaty  beds  of  the  Don  and  those  of  Scarboro', 
except  one  ubiquitous  shellfish.  It  may  be  that  future  excava- 
tions will  settle  which  hypothesis  is  correct;  if,  indeed,  some 
entirely  different  interi)retation  may  not  be  put  ujjon  the  facts 
described. 

Two  very  interesting  articles  have  appeared  recently,  one  by 
Professor  Chamberlin  in  the  Journal  of  Geologv,  the  other  by 
Mr.  Warren  Uphani  in  the  American  Geologist,  referring  to  the 
succession  of  glacial  deposits  in  America,  and  mentioning  the 
Toronto  inter-glacial  beds  in  that  connection.  Professor  Cham- 
berlin gives  the  "Toronto  Formation"  tentatively  an  independent 
position  as  the  possible  equivalent  of  Geikie's  Neudeckian,'  and 
places  it  in  the  interval  between  the  lowan  and  Wisconsin  sheets 
of  till.  Mr.  Uj^ham  places  the  Toronto  inter-glacial  beds  in  a 
somewhat  similar  position,  but  looks  upon  them  as  only  in  a 
limited  sense  inter-glacial,  "  since  they  lie  between  deposits  of 
glacial  drift ;  but  they  seem  better  referred  to  moderate  oscilla- 
tions of  the  ice  boundary  during  its  general  retreat  after  the 
lowan  stage,  that  is,  to  a  time  during  the  Wisconsin  or  moraine- 
forming  stage  rather  than  to  distinct  glacial  epochs."*  He  sup- 
ports this  view  by  a  statement  as  to  thinning  out  of  the  beds  of 
till  between  Scarboro'  and  Toronto,  suggesting  the  nearness  of 
the  ice  border;  and  finds  the  deposits  "quite  inexplicable  on  the 
hypothesis  that  these  till  formations  record  great  readvances  of 
the  ice,  as  either  to  the  lowan  stage  or  to  the  Wisconsin 
moraines.  "3 

In  regard  to  the  thickness  of  the  sheets  of  till  it  may  be 
mentioned  that  they  vary  greatly   in   this   resjject  within   short 

'JdURNAi,  OK  Gkoi.ogy,  Vol.  III.,  No.  3,  pp.  273-275. 
"Am.  Geol.,  Vol.  XV.,  No.  5,  p.  289,  etc. 

3  11)1(1.,  p.  200. 


639    JONONJO  GLACIAL  AND  INTER-C, I.ACLIL  DEPOSITS. 

distances  both  at  Scarboro'  and  along  the  Don,  but  by  no  means 
always  in  the  sense  of  thinning  out  towards  the  west.  For 
instance,  the  middle  till,  the  lowest  visible  at  Scarboro',  is  there 
generally  less  than  thirty  feet  thick  and  for  a  mile  or  more 
scarcely  averages  five  feet  in  thickness  ;  but  at  the  Dutch  Church, 
where  the  subglacial  debris  has  been  crowded  into  a  deep  valley, 
it  reaches  a  maximum  of  seventy  feet.  The  same  bed  of  till  at 
the  Don  brickworks  is  thirty-five  feet  thick,  and  a  little  farther 
south,  between  the  Winchester  street  bridge  and  Danforth  avenue, 
is  apparently  ninety  feet  thick. 

The  upper  till  at  Scarboro',  so  far  as  I  have  measured  it,  runs 
from  twenty  to  thirty  feet  in  thickness  ;  but  at  Moore  Park  Sta- 
tion, less  than  a  mile  north  of  Taylor's  brickyard  it  is  forty-five 
feet  thick,  and  at  V'ork  Mills,  three  or  four  miles  northwest,  is 
nearly  sixty  feet  in  thickness. 

In  reality  the  difference  in  thickness  of  the  drift  at  Scarboro' 
and  the  Don  is  due  rather  to  the  greater  or  less  development  of 
the  inter-glacial  beds  than  to  the  thickness  of  the  till. 

If  these  inter-glacial  dejjosits  were  formed  during  slight  oscil- 
lation of  the  ice  margin,  one  would  sui)posc  that  drifting  ice 
floes  or  even  bergs  would  have  been  active  on  the  waters  of  the 
time,  transporting  bowlders  and  other  materials,  which  should 
be  imbedded  in  the  clays  and  sands  of  the  lake  bottom  ;  but 
neither  Dr.  Hinde  nor  the  present  writer  has  been  able  to  find 
stones  of  any  kind  in  the  140  feet  of  fossiliferous  beds  at 
Scarboro'. 

The  case  of  the  Alaskan  glaciers  cited  in  the  article  men- 
tioned' is  in  reality  not  at  all  analogous  to  the  conditions  pre- 
vailing at  Toronto  during  the  earlier  inter-glacial  time.  In  Alaska 
the  Japan  current  brings  comparatively  warm  moist  air  right  up  to 
latitude  60°;  while  the  highest  mountains  in  North  y\merica  rise 
a  few  miles  inland,  their  icy  flanks  intercepting  the  moisture- 
laden  winds  from  the  Pacific  and  causing  a  tremendous  snowfall 
in  a  region  where  the  snowline  is  only  2000  feet  above  sea  level. 
If  Mt.  Fairweather,  Mt.  St.  Elias  and   Mt.  Logan  were  leveled, 

•  Ibid.,  p.  278. 


■////•;  JOURNAL  OF  GEOLOGY.  640 

how   long  would   the  Mahispina  and  other  Alaskan  glaciers  hold 
their  ground  ? 

At  Toronto  during  one  part  of  this  inter-glacial  time  we  had 
a  climate,  judging  bv  the  flora  and  fauna,  far  milder  and  drier 
than  that  of  Alaska;  and,  nothing  that  can  be  called  a  mountain 
rises  between  this  and  Hudson  liay.  The  inter-glacial  time  was 
long  enough  not  only  to  allow  of  the  deposit  of  the  thick  beds 
of  sand  and  clay  that  have  been  described,  but  to  allow  the  great 
body  of  water  in  which  they  were  formed  to  be  drained  to  a  depth 
of  one  hundred  and  fifty  feet,  and  the  new  land  surface  to  be 
deeply  eroded.  At  the  Dutch  Church,  for  instance,  a  valley  was  dug 
a  mile  in  width  from  edge  to  edge  and  a  cjuarter  of  a  mile  wide 
at  the  lowest  level  exposed  by  Lake  Ontario.'  All  of  this  must 
have  demanded  time  and  plenty  of  it.  J^an  any  one  believe  that 
meantime,  while  elms  and  oaks  and  mai)les,  not  to  mention  the 
papaw,  were  growing  along  the  Don,  the  ice-field,  with  no  loftv 
slopes  to  supj)lv  gathering  ground  for  neve,  was  lurking  a  few  miles 
off,  ready  to  advance  and  overwhelm  the  deciduous  forests  ? 

It  has  been  pointed  out  in  a  previous  paper  that  Toronto  lies 
not  more  than  500  miles  from  Hudson  Bay  or  700  from  the  cen- 
ter of  Labrador,  with  no  mountains  intervening.*  There  seems 
no  more  reason  to  assume  that  a  great  ice-field  existed  within  those 
distances  while  the  Don  fossils  were  being  buried  than  there  is 
to  assume  it  at  the  jjresent  day.  As  a  whole,  then,  the  evidence 
at  Toronto  seems  to  support  strongly  the  theory  of  Geikie,  Cham- 
berlin  and  others  as  to  the  distinct  ice  ages  separated  by  mild 
inter-glacial  times. 

The  unfossiliferous  clays  and  sands  lying  between  the  mid- 
dle and  upper  sheets  of  till  and  having  a  thickness  of  at  least 
one  hundred  and  sixty  feet  at  Scarboro',  and  of  forty  at  Toronto, 
indicate  a  second  recession  of  the  ice.  The  absence  of  fossils,  the 
presence,  though  rarely  of  angular  striated  pebbles  in  the 
clay,  and  the  corrugated  and  crumpled  beds  here  and  there 
found  among   the  upper  sandy   layers  suggest  a  cold,   perhaps 

'  See  Suction  of  Scarboro'  Heiglits. 
-Am.  Geol.,  Vol.  XIII.,  p.  92. 


641     TORONTO  GLACIAL  AND  LVTKR-GLACLIL  DEPOSITS. 

Arctic  climate,  iiiiplyiiisj^  perhaps  only  a  long  recession  of  the 
ice,  not  its  complete  removal.  The  ujjper  ])art,  consisting  of 
cross-bedded  sand  aiul  clayey  sand,  seems  (juite  wiilespread,  for 
similar  beds  lying  between  the  rolling  surface  of  till  and  a  lower 
sheet  of  till  have  been  found  on  a  branch  of  the  Don  seven  miles 
north  of  the  city,  at  Pickering  twenty  miles  northeast,  and  on 
the  lake  shore  near  Newcastle  forty  miles  to  the  east.  IL  may 
be  that  fossils  giving  a  hint  as  to  the  climate  in  this  inter-glacial 
jjcriod  will  be  fountl  at  some  ♦^^ime.  The  tooth  of  a  mammoth 
was  found  last  summer  on  the  Don  eight  miles  north  of  the  city 
at  a  point  where  the  stream  flows  over  the  middle  till  and  cuts 
away  banks  showing  stratified  sand  and  in  some  cases  the  uppe 
till  also,  but  the  fossil  may  be  post-glacial  rather  than  inter-glacia 
in  age.  The  same  holds  of  two  mastodon  teeth  found  several 
years  ago,  one  on  the  Don,  the  other  in  a  sand  pit  two  or  three 
miles  east  of  the  city. 

If  Professor  Chamberlin  is  correct  in  assigning  the  fossilifer- 
ous  beds  of  Toronto  and  Scarboro'  to  the  interval  between  the 
lowan  and  Wisconsin  ice  ages;'  then  the  up[)er  stratified  beds 
imply  a  still  later  ice  age,  se})arated  probably  by  a  shorter  and 
less  genial  inter-glacial  time  than  the  former  one.  It  is  however 
possible,  as  suggested  by  Professor  Chamberlin,  for  the  beetle- 
bearing  beds  of  Scarboro'  in  case  they  should  prove  to  belong 
to  a  lower  horizon  than  the  Don  beds,  that  the  fossiliferous  beds 
near  Toronto  are  of  Aftonian  age,  i.  e.,  belong  between  the 
Kansan  and  lowan  sheets  of  till ;  and  that  the  upper  beds  repre- 
sent the  interval  between  the  lowan  and  Wisconsin  ice  sheets. 
The  former  supposition  seems  to  me  the  more  probable,  since 
there  is  some  likelihood  that  the  mild  morainic  sheet  forming 
the  Davenport  ridge  and  upper  Scarboro'  Heights  runs  out  in  the 
neighborhood  of  Toronto,  and  hence  cannot  be  continuous  with 
the  Wisconsin  sheet  to  the  so  ithwest.  Until  the  till  sheet  lying 
to  the  north  and  east  of  Toronto  has  its  western  boundaries 
traced  this  point  cannot  be  settled. 

A  long  halt  in  the  retreat  of   the   last  glacier,  if  not  a  recru- 

"  Journal  Gkoldgy,  Vol.  III.,  No.  3,  p.  273,  etc. 


THE  JOURNAL  OF  GEOLOGY.  642 

(lesccncc  of  glacial  conditions  after  another  interval,  is  indicated 
by  the  great  niorainic  loops  stretching  from  Trenton  westwards 
to  Lake  Huron  and  passing  (as  the  Oak  ridges)  about  eighteen 
miles  north  of  Toronto. 

The  post-glacial  history  of  the  region  near  Toronto  has  not 
yet  been  satisfactorily  worked  out,  though  one  episode,  that  of 
the  Irocjuois  water  as  described  by  Dr.  Spencer,  has  left  its  mark 
very  distinctly  in  the  old  beach  to  the  north  of  the  city,  and 
must  have  had  considerable  importance  as  regards  the  formation 
of  surface  dejjosits. 

Much  of  the  somewhat  loess-like  fine  clayey  sands  of  the 
Humber  valley  may  turn  out  to  be  post-glacial  ;  and  Dr.  Hinde 
supposes  that  the  upper  hundred  feet  of  sand  and  gravel  at  the 
west  end  of  the  Scarboro'  cliffs  are  of  the  same  age ;  but  my 
own  observations  incline  towards  an  inter-glacial  position  for 
these  thick  and  widespread  but  greatly  eroded  deposits.  Similar 
sands  occurring  at  York  Mills  and  other  points  north  of  the  city 
are  undoubtedly  covered  by  the  upper  till,  which  may  simply 
have  been  removed  from  the  more  southern  parts  near  the  lake. 
Unprotected  by  a  layer  of  till  these  sands  are  easily  attacked  by 
wind  and  water  and  superficially  rearranged,  so  that  their  original 
structure  and  relationshij)  becomes  obscured. 

Of  course  the  Don  and  Humber  with  their  tributaries  have 
formed  in  the  lower  sluggish  parts  of  their  courses  alluvial 
deposits  of  clay  and  sand  that  arc  evidently  modern,  and  in  some 
instances  arc  added  to  by  every  spring  flood. 

The  succession  of  events  since  Pliocene  times  in  the  vicinity 
of  Toronto  may  now  be  reviewed  in  order  to  bring  to  a  focus  the 
results  of  the  observations  described  in  this  paper. 

No  Pliocene  deposits  have  been  found  in  this  region,  suppos- 
ing the  earliest  advance  of  the  ice  to  indicate  the  end  of  the 
Pliocene;  but  the  lowest  till  forms  a  carpet  over  the  eroded 
surface  of  the  Hudson  River  shales.  At  the  time  the  earliest 
glacier  advanced  the  Scarboro'  region  formed  a  valley  whose 
hollow  is  now  below  the  surface  of  Lake  Ontario,  and  there  were 
low  hills  where   the   Don  and   Humber  valleys   now  exist,   the 


643    TORONTO  GLACIAL  AND  LWTER-GLACIAL  DEPOSITS. 

highest  observed  level  of  the  shale  being  about  eighty  feet  above 
the  lake  at  Lambton  Mills  on  the  Humber. 

The  retreat  of  the  ice  was  followed  by  a  rise  in  the  water  of 
the  lake  to  a  level  at  least  150  feet  above  the  present  lake, 
depositing  that  depth  of  clav  and  sand  upon  the  unweathered  till. 
The  Scarboro'  water,  as  it  may  perhaps  be  called,  was  then 
drained  off  to  a  point  below  the  present  lake  level,  and  at  some 
points  erosion  took  place  to  a  corresponding  depth.  It  is  possi- 
ble that  the  climate  became  warmer  during  this  period  of  erosion 
and  that  the  Don  beds  were  deposited  afterwards. 

At  the  time  of  the  second  glacial  period  the  toiK)graj)hy  of 
the  region  hatl  greatly  changed.  The  Scarboro'  Heights  already 
had  an  elevation  of  150  feet,  while  valleys  reaching  the  jiresent 
lake  level  had  been  cut  bv  Highland  Creek  and  the  Don,  as  well 
as  by  the  Dutch  Church  stream,  which  now  has  no  equivalent. 
The  retreat  of  the  second  ice-sheet  was  followed  bv  a  rise  of  the 
water  to  a  height  of  280  feet  above  the  present  lake,  the  water 
being  cold  and  lifeless,  and  bearing  ice  floes. 

Once  more  the  lake  was  drained,  at  least  partiallv,  and  erosion 
went  on,  for  the  upper  till  is  found  at  a  sand  j)it  near  the  corner 
of  Bloor  and  Christie  streets  in  Toronto  at  a  level  of  about  120 
feet  above  the  present  lake.  Either  the  period  of  dry  land  was 
short,  giving  no  time  for  the  cutting  of  deep  valleys,  or  the  level 
of  the  lake  of  those  days  was  considerably  above  the  present 
Lake  Ontario,  The  contour  of  the  land  at  the  end  of  this  inter- 
glacial  period  is  more  difficult  to  settle  than  in  the  former  one  ; 
but  it  is  tolerably  certain  that  the  Scarboro'  Heights  had  almost 
their  present  height,  and  that  the  Don  valley  was  much  shallower 
than  at  present,  if  it  existed  at  all. 

The  retreat  of  the  third  ice-sheet  was  followed  as  before  by  a 
rise  of  water.  Lake  Irocpiois  reaching  160  feet  above  the  present 
lake  to  the  north  of  Toronto,  and  about  I  go  at  Scarboro'.  After 
the  draining  of  Lake  Iroipiois  it  is  [)robable  that  the  surface  of 
the  country  presented  much  the  same  rolling  swells  of  till  as  are 
now  found  north  and  cast  of  Toronto;  fo  ,  in  general,  erosion 
has  gone  on  to  a  moderate  degree  only,  e.\ce|)t  where  the  more 


'    .  THE  JOURNAL  OF  GEOLOGY.  644 

powerful  streams  have  cut  out   picturesque   ravines,  such  c.s  arc 
seen  along  the  Don  and  H  umber. 

It  is  probable  that  at  the  end  of  the  first  inter-giacial  period  the 
topograi)hy  had  almost  as  old  an  asjiect  as  at  present,  indicating 
as  long  a  time  for  erosion  as  has  elapsed  since  the  last  ice  age  ; 
but  the  dry  land  stage  during  the  second  inter-glacial  period  was 
apparently  much  shorter.  The  length  of  time  during  which  high 
water  lasted  during  the  two  mild  periods  must  have  been  very 
great  to  allow  the  immense  sedimentary  beds  to  be  deposited  at 
Scarboro'  and  elsewhere,  150  feet  thick  in  the  earlier  period  and 
160  in  the  later.  The  Irocpiois  high  water  stage  after  the  last  ice 
age  was  probably  much  shorter,  since  it  has  left  much  smaller 
sedimentary  deposits. 

It  is  a  notable  fact  that  each  ice-sheet  advanced  api)arently 
during  a  time  of  low  water,  and  was  followed  by  a  stage  of  high 
water ;  whether  this  is  to  be  accounted  for  by  assuming  an  ice 
dam  at  the  foot  of  the  predecessors  of  Lake  Ontario,  or  a  change 
in  the  level  of  the  land  surface  caused  by  the  loading  and  unload- 
ing of  its  ice  burden,  it  is  very  unlikely  that  the  sea  has 
extended  inland  so  far  as  Toronto  since  glacial  times.  The 
numerous  marine  animals  found  as  fossils  lower  down  on  the  St. 
Lawrence  and  Ottawa  would  hardly  have  stopped  short  without 
reaching  the  Iroquois  bay,  if  that  had  been  a  body  of  salt  water, 
in  communication  with  the  Gulf  of  St.  Lawrence.'  However,  no 
fresh  water  forms  have  been  found  on  its  beach,  so  that  the  evi- 
dence is  only  negative. 

The  Scarboro'  beds  give  very  instructive  evidence  as  to  the 
comparatively  slight  erosive  power  of  glaciers.  Except  near  the 
east  end  of  the  section,  where,  as  suggested  to  me  some  time 
ago  by  Mr.  J.  H.  Tyrrell,  the  ice  front  began  to  rise  upon  the 
higher  ground  during  the  second  advance  and  crumpled  and  con- 
torted the  clay  beds,  there  is  no  very  striking  disturbance  even  of 
the  stratified  sand,  though  here  and  there  portions  of  the  sand 

'  Two  marine  .shells  have  lieen  picked  up  on  the  Iroquois  beach,  but,  as  suggested 
by  Dr.  Dall,  to  whom  they  were  submitted,  they  have  almost  certainly  reached  tliat 
position  by  liuman  agency. 


645     rORONTO  GLACIAL  AND  LXTER-GLACLIL  DEPOSfTS. 

arc  tilted  out  of  place.  The  upi)er  layer  of  till  rests  in  some 
places  on  crumpled  beds  of  sand,  but  more  often  one  sees  little 
trace  of  disturbance.  One  might  almost  describe  the  till  as  a 
lubricant  allowing  the  ice-sheet  to  glide  easily  over  the  inequal- 
ities of  the  surface. 

A.  P.  Coleman. 


